Design and experiment of a single needle vibrating pneumatic pepper precision seed dispenser

Objective Seedling transplanting is a common method used in pepper planting.Aiming at the phenomenon of missing seeding in pepper hole tray，a single needle vibrating pneumatic pepper precision seed discharging device was designed to replace the holes in the hole tray and improve production efficiency. Method Taking the seeds of “Xingshu Wrinkling Spicy No.2” pepper as the research object，based on the physical characteristics of the seed，the vibration feeding mechanism，the linear carrying mechanism and the control system of the seed discharging device were analyzed and designed，and a test bench was built.The vibration frequency of the seed box，the vacuum degree of the air suction needle and the diameter of the air suction needle were taken as the test factors，and the single seed discharge rate was taken as the test evaluation index.The specific values of the vibration frequency of the seed box，the vacuum degree of the air suction needle and the diameter of the air suction needle were determined to be 77-89 Hz，15-35 kPa and 0.6-0.8 mm，respectively.On this basis，the response surface test is carried out，and the analysis of variance，response surface analysis and optimization of test factors are carried out by using Design-Expert software. Result The influencing factors of seed discharge per particle rate were determined from the largest to the smallest as vacuum degree of suction needle，diameter of suction needle and vibration frequency of seed box.The optimal operating parameters of the seed discharge device were obtained as vacuum degree of suction needle 27 kPa，diameter of suction nozzle 0.7 mm and vibration frequency of seed box 85 Hz.The seed discharge per particle rate was 98.25% in prototype test. Conclusion The experiment shows that the single needle vibrating pneumatic pepper precision seeding device works stably and has high single seed rate，which can meet the requirements of pepper precision seeding operation.